S2R+ cells were fixed with 1% formaldehyde for 3 min at room temperature, and harvested in SDS buffer resuspended in RIPA buffer (140 mM NaCl, 10 mM Tris-HCl [pH 8.0], 1 mM EDTA, 1% Triton X-100, 0.1% SDS, 0.1% DOC), and lysed by sonication. The lysate was cleared by centrifugation, and incubated with respective antibodies overnight at 4ºC. Antibody complexes bound to protein G beads, were washed once with 140mM RIPA, four times with 500mM RIPA, one with LiCl buffer and twice with T.E buffer for 10 minutes each at 4ºC. After checking enrichment the recovered DNA was converted into libraries using NebNext Ultra DNA library preperation kit, following manufacturer's protocol NebNext UltraII